DE3045741A1 - PLASTIC CAN WITH A RING SHAPED INNER EDGE AND METHOD FOR REMOVING THIS CAN FROM A MOLDED CORE - Google Patents

Description

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Dipl-Ing. Dipl.-Chem. Dipl.-Ing

E. Prince - Dr. G. Hauser - G. Leiser

Ern & Berger-, route 19

8 Munich 60

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JOHN W. VON HOLDT December 4, 1980

6864 Lexington

Niles, Illinois 60648 / USA

Our reference: V 751

Plastic can with an annular, inwardly protruding Edge and method of removing this can

from a mold core

Lids of paint cans or cans and paint buckets can be removed by breaking open an outer flange of the lid can be easily removed from the can rim with a screwdriver or the like. However, if the lids are on the If the edge of the can is caught, they have a great deal of resistance to accidental opening due to a shock when falling or similar.

According to the invention is an improved can or can created. This jar can be used in conjunction with the lids described in a previous application are, as well as with other lids, to obtain improved, sealed containers for paint or other materials, which have the particular advantage that they can be used on existing industrial automatically operating machines can be used to fill and close paint containers,

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At the same time, the invention has the particular advantage of the sealing strength of the sealed with the lid Dose achieved as noted in the above-mentioned application.

The invention is a plastic box with a Created bead at its opening, the bead forming means for engagement with a can lid, which is connected to the beaded edge for sealing.

According to the invention, the inner wall of the can forms an annular, inwardly projecting edge which extends from the Bead edge is arranged adjacent to this at a distance. The edge extends around the inner periphery of the can and it forms an annular, inwardly directed tip. This increases the benefits of an Ring strength created for the can adjacent to its opening, while at the same time the ring-shaped edge to the Preventing splash and can be used as part of wiping a brush in the can what the Substantially reduced spillage of paint or the like from the can during use.

Preferably the inner tip is less than about 25 Imra (1 inch) from the outermost part of the can bead, usually this measurement can be about 6.3mm (1/4 inch) or of this order of magnitude. It is also preferred for the annular tip to be so thin that it essentially forms a line in order to improve the wiping properties of a brush.

Further, the surfaces of the inwardly projecting edge extend from the annular tip to the inner wall of the Can preferably concave, in particular the area between the tip and the can bulge.

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The lid used on the can preferably forms first and second transversely arranged annular ones Walls to form an annular, open recess, the second annular wall being the outer boundary the recess forms. The first annular wall defines the inner boundary for the recess, and it is preferred an integral segment of the can end that is on opposite sides with other portions of the can end connected is.

A third annular wall of the lid can be arranged outwardly from the second annular wall, the second and third annular walls in turn having an annular hooking slot therebetween form, which receives and holds the beaded edge of the lid. The second wall can also be an externally arranged annular one Carry projection that forms a surface that points to the annular hooking slot and the one Forms angle to the plane of the second annular wall, which can be approximately 80 ° to 100 °. This annular protrusion is intended to touch and hold a mating projection of the can bead that is inside the hooking slot is arranged.

The second wall also forms below the one arranged outside annular projection a surface whose shape is complementary to the shape of the side of the annular edge pointing to the mouth of the can. This results in an annular adjacent sealing surface between the upper side of the edge and the second wall may be formed, which extends substantially to the annular Tip extends out for improved sealing of the container.

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The third ring-shaped wall can also form an inwardly arranged projection, which with an outwardly Pointing projection of the Doesenwulstrandes can come into a hooking engagement in the hooking slot is arranged for an additional seal of the two parts.

Preferably, the first annular wall of the can lid can also be used for preferential pressure evasion or butt adjacent to the can lid, as described in the aforementioned application, with the Result that the second annular wall in such circumstances for an improved sealing strength relative remains immobile.

The second annular wall can be thicker than the first annular wall, which is the preferred evasion of the first Wall supports.

Preferably, the mating surface of the second wall resting against the inwardly directed edge is in shape convex to preferably match the concave shape of the top of the inward facing edge.

If desired, the can bead can also have an annular, outwardly protruding edge that extends around the outer beginning of the can bulge and forms an annular, outwardly pointing tip. A surface of the can bead can be opposite to the direction of the can mouth extending outwardly from the tip, having a generally planar annular shape. The generally planar, annular shape of the outer end of the can bead is for improved sealing properties free of mold parting lines, whereby the mold parting

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line is preferably arranged at the outwardly pointing annular tip of the can bead edge. This improves the sealing properties of the container and it is possible because of the shape of the generally flat, annular surface, and the inner surface of the can bead can be suitably sized to accommodate its removal from one Shape even if the parting line is located at the annular, outward-pointing tip.

Another basic idea of the invention is a device for removing the molded can from a mold core. This The mold core has an ejector device for pressing against the inside of the can and any pneumatic means for a Pressurizing the interior of the can to facilitate longitudinal removal of the can from the core.

According to the invention, the supply with a pressurized flowable medium is provided together with channels. The channels lead the pressurized medium through the mold core between the supply source and the inward-facing edge of the can, as previously described. Thus, a source is one among Pressure standing flowable medium provided that the The plastic can expands circumferentially adjacent the edge to allow the removal of the can from the core by the Ejector and pneumatic pressure to facilitate.

The channels for the source of the pressurized flowable medium are narrow enough in size to accommodate the To prevent the liquid molding mixture from flowing into these channels during the molding process. For example

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the channels for the flowable medium have a width of approximately 0.0127 mm to 0.0508 mm (0.0005 to 0.002 inch).

In the following, exemplary embodiments of the invention are described, which are shown in the drawing. In the Drawing are:

Fig. 1 is a perspective view of a can according to the invention with its lid,

Fig. 2 is a perspective view of another can according to the invention with its lid,

3 shows part of an enlarged longitudinal section through part of the can and the lid of Fig.l,

Fig. *) Part of an enlarged longitudinal section through the can and the lid of Fig. 2,

Fig. 5 is a longitudinal section through a mandrel for Production of the can of Fig.l in the position in which the can is just formed on the mold core has been,

Fig. 6 is a longitudinal section through the mandrel and the box of Figure 5, the can when removed from the Mold core shows, and

Figure 7 is a substantially enlarged longitudinal section showing the lip of the can of the present invention and its relationship pointing to the mandrel.

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Fig. 1 shows a can or can 10 with a straight wall which is used in an industrial dye filling machine for Filling cans can be handled. This can carries a lid 12. Both the can 10 and the lid 12 are formed from individual molded pieces of thermoplastic material.

As shown in Figure 2, the invention can be used with a conical can or liner 13 and its lid Ik . The can 13 and its lid 14 can, as in the can of Fig.l, be formed from any shapes of the can lip or the can bead and from a closure system described here or from shapes equivalent thereto. According to FIG. 3, the design of the can closure uses the basic ideas of the patent application

although the illustrated cover 12 is free of any radial tabs in the particular case described here Embodiments is because such tabs for the described embodiment for use as a paint can have been deemed unnecessary.

The can 10 forms an annular lip or annular rim 16 with an enlarged top End as shown.

The lid 12 includes a first annular wall 18 and a second annular wall 20, which in turn define an open recess 22, in the radial if desired Tabs can be added.

A third wall 24 of the lid 12 can be outside of the second annular wall 20 may be arranged. This wall

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in turn forms an annular hooking slot with the wall 20 in which the bead 16 according to FIG Representation is to be included, the bead 16 being received in this hooking slot and held therein will.

The second wall 20 also carries an externally arranged, annular projection 26. This projection 26 forms a surface 28 which faces the annular hooking slot 16 and which, if desired, forms an angle of substantially 80 ° to 100 ° to the plane of the second annular wall 20 forms. This annular protrusion 28 must come into contact with a matching projection 30 of the can bead 16 and this as shown when the bead is arranged in the hooking slot.

In accordance with the invention, the can 10 has an inwardly projecting edge 32 which is adjacent to but spaced from the bead 16. The edge 32 extends around the inner circumference of the can 10 and it forms an inwardly projecting tip 3 ¹ J. As previously mentioned, generates the edge 32 of the can, adjacent its opening has a ring strength, and it forms an inner in the can Part for wiping off a brush.

Furthermore, the annular edge 32 serves as a spray guide to prevent the contents of the open can from being released splashing out of the opening as the inwardly projecting edge 32 is prone to any splatter in a radial direction inwards towards the center of the can, where they return to the can without escaping

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content can fall and get there with this again can unite. In particular, the tip 34 of the Edge 32 about 3.175mm or about 4.762mm (1/8 or 3/16 Inches) from the top surface 36 of the desert edge 16 of the Can be arranged remotely.

The surfaces 38, 40 of the annular edge 32 are preferred concave. The surface 38 is shaped so that it mates with an associated surface 42 of the second wall 20, which is below the surface 28 of the annular projection is arranged to form an annular, mating sealing surface between the walls 38,42 which extend preferably extends substantially to the tip 34. Accordingly, an expanded seal is provided between the bead 16 of the can and the lid 12. she begins adjacent to the tip 34 and extending over the Cross-sectional area approximately of the surface of the bead edge 16 upwards and over the upper surface 36 of the bead edge out. As a result, the can and the lid of the invention have excellent sealing properties. At the same time, they show great resistance to the accidental removal of the cover by a push Dropping the can or the like is exerted.

The first wall 18 may form the outer part of an annular recess 44, the annular innermost wall 46 forms the inner wall of the recess 44. When applying a compressive force to the can and the lid of Fig.3 accordingly gives way to the wall 18, where it absorbs the compressive force without displacement of the wall 20 or 24, so that the seal of the bead 16 of the can is retained.

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Preferably, the second annular wall 20 of the lid 12 has a greater thickness than the first annular wall 18, which is the selective deflection of the first annular wall 18 upon the application of an impact to the closed can lid relieved, while the walls 20 and 2 * 1 relatively rigidly in engagement with the bead l6 of the can remain.

In Figures 2 and 4 is a conical can 13 or a conical sleeve in contrast to the can 10 or sleeve with straight walls and a modification of the closure of this invention. Nevertheless, both types of closure or a further modification can be interchangeable be used with cylindrical cans or with conical cans.

As in the previously described embodiment of FIG. 3, a can is shown in FIG. 4 which has a bulging edge 16a to which a can lid 14 is attached. The lid 1 * 1 forms a first wall L8A and a second wall 20a of a shape which is similar to that of the embodiment previously described with the exception that the central portion 4 * Yes of the lid I ¹ J in a pressed down state with respect to the peripheral portion the lid 14 remains, as shown in Fig. ¹ I, because none of the wall 46 corresponding wall exist. This arbitrary variation still forms a wall 18a, which can move in a preferred manner for the wall 20a, but with the mass of the cover at the middle section 44a, which is a plane including a lower section of the wall 20a instead of an upper section of the corresponding wall 20 in FIG Fig. 3 assumes.

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For a puncture similar to the one described above The exemplary embodiment is a third annular wall 24a intended. An annular inwardly protruding edge 32a may be similar in shape to the annular edge 32 and exist for the same purpose.

In this embodiment, the bead 16a of the can forms an outwardly pointing annular edge 46a which ends in an outwardly pointing annular tip which is designated by the same reference number. The area the bead of the can extending outwardly from the tip 46a opposite the direction of the can opening, forms a generally planar annular surface that is opposite to the shape of the inner surface 50 of the bead rim 16a of the can is suitable to form the dividing line for the beaded edge of the can, which is arranged at another point is than the generally flat surface 48 and the outer end 52 of the bead 16a of the can. The dividing line, which is produced on the bead 16a of the can by the mold in which the bead was made, may be located at the tip 46a so that the annular surfaces 48 and 52 for maximum sealing properties of portion 54 of can lid 14 can be smooth and clean to fit snugly against surfaces 48 and 52.

In the embodiment of Figure 3, the dividing line 56 is often arranged on the bead 16 of the can as an annular line at the outer end 36 of the bead 16. In many cases it may be desirable to move the parting line to the annular tip 46a while the special shape of the bead edge l6a of the can an easy and reliable removal of the bead edge l6a from his Shape facilitated even if the parting line is located away from the outer end of the bead edge 16a, for example at the top 46a.

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Annular projections 58,58a on the outside of the cans 10,13, adjacent the corresponding bead edges are provided as barriers to against the respective outer walls 24,24a in the event of severe bending of the container to serve as an additional support part against the lid bursting off.

FIGS. 5 to 7 show a device with a mold core for the production in particular of a can with a straight wall, for example a can 10 shown here Invention. The corresponding mold that surrounds a mold core 16 during the molding process is not shown, however, it can be of conventional design.

It is a pneumatically operating device for removing a can is shown, in which the edges 32,32a a Can with a straight wall serves as a seal to maintain pressure against the mandrel acts when the can is removed from the mandrel by compressed air.

The mold core separated from half of a mold cavity 60 leaves the freshly formed can 10 arranged on its outside lying free.

An ejector 62 has a shaft for pressure against the inside of the can for support upon removal of the can from the core 60. The shaft 62 may be only about 9.53 now (3/8 inch) in diameter and it serves for a safe removal of the can from the core in an automated operation. A large part the removal force is provided by pneumatic means as described below.

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The shaft 62 reciprocates in a chamber 64. The chamber 64 is formed in the mold core 60. The inner The end of the shaft 62 forms a piston 66. The chamber is closed at its lower end by a seal 68.

O-rings 70 and 72 are provided around the circumference of the piston 66 and the shaft 62 at the upper end of the chamber 64, respectively.

An inlet line 73 for compressed air is connected to the lower part 74 of the chamber 64 for pushing out the rod 62 outside by compressed air when pressing the can 10 from the mold core 60 in connection. A line 76 for compressed air is provided to the piston 66 and the stem 62 by the application of pressure to the upper part 78 of the chamber 64 so that the shaft 62 can be reciprocated for removal of cans in the molding process.

A pressure line 80 is connected to a cylindrical channel in the mold core 60, in which the shaft 62 is and go. The upper part 84 of the rod 62 has a smaller diameter tolerance; to the diameter of the channel 82 as the lower part, so that a sealing effect against the compressed air from line 80 when rod 62 is in its retracted position. But when the rod 62 begins to slide forward, thus providing a larger flow conduit for pressurized air from the conduit 80 is provided for a flow into the space between the can 10 and the mold core 60. The compressed air tries that Pressing the can and pushing it outward from the mold core.

A fourth compressed air line 86 is connected to an annular cutout 88 in the mold core 60. The cutout

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serves to accommodate the annular, inwardly extending edge 32 of the can 10, as shown in FIG. The annular cutout 88 includes an annular portion 90 which may be a split ring of a material retained in the core 60 when the annular cutout 88 is formed. The ring is then reattached in place. The split ring 90 is reattached in the annular cutout 88 to define flow paths 92.9 * 1 around the inner peripheral surfaces of the split ring 90, the flow paths 92.9 * ¹ preferably having a generally annular shape except for the necessary support members 96 arranged to support and hold the split ring. The flow ^{paths 92, 9 1} J surround the support part 96 so that a free flow of air through the flow paths around the support parts 96 is made possible.

Preferably, the annular flow channels 92.94 have a width or thickness of about 0.0127 mm to 0.0508 mm (0.0005 inches to 0.002 inches) and typically a width or thickness of about 0.025 ¹ J mm (0.001 inches) , their optimum thickness depending on the viscosity of the molding mixture and the pressure of the molding.

A thickness is preferably selected which is sufficient for an air flow into the inner surface area 102 of the can 10 allows, while at the same time being sufficiently narrow that the molding mixture is prevented from doing so to a significant extent Scope to flow into the air channels 92,94 during the molding process.

To facilitate the removal of the meniscus l6 of the can 10 of the mandrel can thus compressed air through the line 86 into the annular branch line flow 98, from which they laugh in the generally annular flow paths 92.9 ¹ I to the inner Umfangsf of the split ring

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90 flows. From here the air exits through openings in contact with the inner surface of the can 10, with compressed air in the general area of the inner can surface 102 occurs on the split ring 90 and on the associated one Parts of the mold core 60 is applied.

A split molding ring 10 ¹ I shown in FIG. 5, which is used during the molding process for the formation of the outer surface of the bead 16 of the can 10, is withdrawn during the removal of the can during the molding process, as shown in FIG. Therefore, when there is pressure in the flow channels 92 and 94, the bead 16 and the inner annular projection 32 of the can 10 can be pressed outward by the force of the compressed air by stretching. At the same time, compressed air flowing through the line 80 according to FIG. 6 presses the can 10 from the mold core to the outside. This effect is facilitated because the WuI strand 16 and the annular projection 3? are at least partially outside of the annular cutouts of the mold core which form these parts during the molding process.

Typically, the pressure of the compressed air in each of the lines 73, 76, 80 and 86 is about 5.62 to 8.44 kg / cm ² (80 to 120 psi), with a typical pressure being about 7.03 kg / cm ² ( 100 psi). However, the individual pressures of each line can be adjusted for best results in any particular situation in the molding process.

While a variety of molding compositions according to the invention can be used, a special and satisfactory molding mixture is the polyethylene resin, that from Dow Chemical Company under the number 12065

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on sale is. If desired, two to six weight percent filler material can be used to reinforce the resin material be made of fiberglass.

According to the invention is a plastic box with an annular, inward-facing ring was created near its beaded edge, which both as a ring to avoid a spray as well as a part for wiping off a brush and which also serves to increase the ring strength to reinforce the plastic box. With this invention, the cans can easily be placed on a non-collapsible Core can be molded, even if the cans have straight walls, with a simple, non-collapsible one Core for an effective, quick form process; is used with a shape that is only a slight Maintenance needed.

The above description is only given as an example and does not serve to limit the invention, which is shown in FIGS Claims is expressed.

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Claims (4)

Dipl.-Ing. Dlpl.-Ghem. Dipl.-lna E. Prince - Dr. G. Hauser - G. Leiser Ernsbergeretrasse 1Θ 8 Munich 60 JOHN W. VON HOLDT December 4, 1980 Lexington Niles, Illinois 6064g / USA Our reference: V 751 / Patent claims ( 1. \ Plastic box with a beaded rim at its opening, ^ ¹ * - 'whereby the beaded rim forms means for engagement with a can lid in a sealing fixed connection to the lid, characterized in that the inner wall of the can has a ring-shaped inwardly projecting edge which is adjacent to, but spaced from, the bead edge so that the edge extends around the inner circumference of the can and forms an annular, inwardly directed tip to provide increased hoop strength for the can adjacent its opening. 2. Can according to claim 1, characterized in that the annular tip located less than 25.4mm (1 inch) from the outermost portion of the can bead and that the annular tip is substantially linear. We / na 130035/0524 3. Can according to claim 2, characterized in that the surfaces of the inwardly facing surfaces extending from the annular tip to the inner wall of the can Edge have a concave shape. 4. plastic jar with a beaded rim at its opening, on which a plastic can lid is attached in a sealing manner to the beaded edge of the can, thereby characterized in that the inner wall of the can has an annular, inwardly projecting edge which is contiguous to the bead edge, but is arranged at a distance therefrom that the edge extends around the inner circumferential surface of the can and an annular, inwardly pointing tip that forms the lid has first and second transversely extending annular walls defining an annular open recess form that the second annular wall forms the outer boundary for the recess that the first annular wall represents the inner boundary for the recess and forms an integral segment of the can lid, the segment being connected on opposite sides to other parts of the can lid, that a third transversely extending annular wall disposed outside the second annular wall is that the second and third annular walls in turn have an annular interlocking slot between them form, which receives the beaded edge of the can and holds that the second wall also has an outside disposed annular projection defining a surface facing the annular interlocking slot and which forms an angle to the plane of the second annular wall that the annular projection with a matching projection of the hooking slot 130035/0524 arranged can bead is in contact and this maintains that the second wall also has a surface below the externally disposed annular projection forms, the shape of which is complementary to the shape of the side of the annular edge, the surface to the Can opening points to an annular, adjacent sealing surface between the outside of the edge and the to form a second wall which extends substantially to the apex that the third wall has an interior Has projection that engages with an outwardly facing projection of the can bead, which is arranged in the hooking slot, and that the first annular wall for preferential evasion is suitable in the event of an impact adjacent to the can lid, whereby the second wall under such Circumstances remains relatively immobile for improved sealing strength. 5. Can according to claim 4, characterized in that the surface of the extending from the annular tip to the inner wall and facing the can opening inwardly protruding edge is concave in shape and that the mating surface of the second wall of the can lid accordingly has a convex shape. 6. Plastic can and lid according to claim 4 _S, characterized in that the first wall of the can lid forms the outer surface of an annular groove formed in the lid. 7. jar and lid according to claim 4, characterized in that that the bead of the can has an outwardly facing annular edge, which in an outwardly facing annular edge Tip ends that the surface of the can bead 130035/0524 which extends to the outside of the document opening, defines a generally planar annular surface opposite the shape of the inner surface of the can bead is suitable to allow a parting line for the can bead located somewhere else than on the generally flat surface and on the outer end of the can bead, which is an easy one Allowing for losing weight from a shape. 8. Can and lid according to claim 7, characterized in that the mold parting line for the can on the outside pointing tip of the Dosenwulstrandes is arranged. 9. Can and lid according to claim ^, characterized in that that the second annular wall is thicker than the first annular wall. 10. Plastic box with a beaded edge at its opening, wherein the bead means for engaging a can end in sealing fixed connection therewith Forms bead, characterized in that the inner wall of the can is an annular, inwardly facing Forms edge, which is arranged adjacent to the bead edge, but at a distance from this, that the edge extends around the inner surface of the can and has an annular, inwardly pointing tip to provide ring strength to raise the can adjacent to its opening, the can bead also having an annular, has outwardly protruding edge which extends around the outer circumference of the can bulge and an annular, outwardly pointing tip forms that surface of the can bead which extends from the tip opposite to the direction the can opening extends outwardly has a generally planar, annular shape and that the generally flat, ring-shaped surface and the outer end of the can bead free of mold separation lines for 130035/0524 are improved sealing properties. 11. Can according to claim 10, characterized in that the mold parting line mark on the outwardly pointing, annular Tip of the Dosenwulstrandes is arranged. 12. Can according to claim 10, characterized in that the Can lid is sealingly connected to the beaded edge that the can lid inner and outer transverse Has ring walls in order to form an annular hooking slot therebetween so that the outer wall has an annular, inwardly extending projection which detachably engages the outwardly facing edge stands, and that the inner wall has an annular, inwardly facing projection for engagement with a forms the inner part of the can bead. IJ. Can according to claim 10, characterized in that the annular tip of less than 25, ¹ inun (1 inch) is spaced from the outermost part of the Dosenwulstrandes and that the annular tip is substantially linear. I ¹ I. Can according to claim 10, characterized in that the surfaces of the inwardly pointing edge extending from the annular tip to the inner wall of the can are concave in shape. 15-box according to claim l4, characterized in that a Can lid is sealingly attached to the rim of the can, that the can rim is held in an anchoring slot formed by inner and outer annular Walls of the can lid is formed that the inner annular wall also has an externally arranged, annular projection carries a surface 130035/0524 which points to the ring-shaped hooking slot, making an angle to the plane of the inner annular Wall forms that the annular projection with a arranged in the hooking slot mating projection of the can bead is in contact and holding engagement that the inner walls are also below of the externally arranged annular projection form a surface whose shape is complementary to the shape of the Side of the annular edge is towards the can opening pointing to an annular, adjacent sealing surface to form between the outside of the edge and the outer wall, extending substantially towards the tip extends, and that the outer wall forms an internally arranged projection, which with an annular protruding Edge can come into hooking engagement, which is arranged in the hooking slot. 16. Plastic can lid for attachment to the beaded edge a plastic box, characterized in that the Lid has first, second and third transversely extending annular walls that the first and second annular walls between them form an annular open recess that the second and third walls form an annular hooking slot on the outside of the recess and are suitable are to hold a beaded edge of a plastic can in a hooked, sealing fastening engagement, that the first wall forms an integral segment of the can lid with opposite sides with other portions of the can lid are connected that the first annular wall has a thickness less than the second annular wall has a preferential deflection by the first annular wall upon impact 130035/0524 adjacent the can bead to facilitate what causes the second wall, in such circumstances to remain relatively immobile for improved sealing strength. 17 · Can according to claim 16, characterized in that the second annular wall carries an externally disposed annular projection defining a surface which to the annular hooking slot and an angle of 80 to 100 ° with the annular protrusion for contact and retention with the mating one Projection of the Doesenwulstrandes is suitable, which is arranged in the hooking slot. 18. Plastic can lid according to claim 17, characterized in that that the third annular wall forms an internally disposed projection which is suitable with an outwardly pointing projection of the can bead edge arranged in the hooking slot into hooking engagement get. 19. Plastic box according to claim l8, characterized in that that the can has a beaded edge arranged in the hooking slot, that the inner wall of the can has an annular, has inwardly protruding edge, which is arranged adjacent to the bead edge, but at a distance from it is that the edge extends around the inner circumference of the can and is an annular, inwardly facing Forms tip and that the second wall forms a surface which is in intimate engagement with the side of the protruding Edge that extends from the adjacent tip to the can bead. 130035/0524 20. Apparatus for removing a molded can from a mandrel with an ejector for a pressure against the interior of the can to remove the can from the core, the core having a cutout for receiving the part formed on the can and projecting inwardly from it through the supply of a pressurized flowable medium and channels for the supply of the flowable medium passing through the core between the supply of the pressurized flowable Medium and the inwardly protruding part are in communication to form a pressurized flowable medium for a circumferential expansion of the plastic can adjacent to it guide the part to facilitate removal of the can from the core by the ejector, wherein the channels are sized sufficiently narrow to permit substantial flow of the flowable molding mixture to prevent in the channels during the molding process. 21. mold core and box according to claim 20, characterized in that the channels for supplying the flowable medium have a thickness of substantially about 0.0127 to 0.0508 mm (0.0005 to 0.002 inches). 22. Molding core and plastic box according to claim 21, characterized characterized in that the channels for supplying the flowable medium are generally round in shape have and are arranged in the cutout. 23. Molding core and plastic box according to claim 22, characterized characterized in that the channels for supplying the flowable medium are formed around a separate ring, 130035/0524 • a · which was originally removed and then reattached in the channel for supplying the flowable medium is. 2H . Molding core and plastic can according to Claim 20, characterized in that the ejection device is formed by a piston which works in a cylinder formed in the molding core, and that pneumatic pressure means are used to advance and retract the piston. 25 mold core and plastic box according to claim 24, characterized in that that the ejector is mounted in a cylindrical channel in the mold core, that the outer End of the ejector has a larger diameter than an inner part of the ejector, by one Complete air flow through the cylindrical duct, and that a pneumatic line is connected to the cylindrical duct is connected in the mold core, whereby an advancement of the ejector the opening of a flow path for a pneumatic pressure through the pneumatic line into the space inside the box and on the outside of the The mold core opens to make it easier to remove the can, 26. A method of removing a molded can from a mandrel, the core forming a cutout in the an inwardly protruding part of the can is received, characterized by pressurizing the Interface between the mandrel and the can adjacent to the cutout and by a separate one Pressurizing the interface between the outer end of the mandrel and the can to cause the inwardly protruding part of the can is pushed out of the cutout and that the can of the Mold core is pushed out. 130035/0524 27. The method according to claim 26, characterized in that
that the can is a straight walled can and that
the inward protruding part of the can one after
is inwardly protruding edge, which edge, when removed from the recess, serves as a pressure maintaining seal which acts against the mold core when the can is removed from the mold core by compressed air. 28. The method according to claim 27, characterized in that a mechanical ejection device also for pressing out acts against the inside of the can bottom to remove the can from the core. 29. Apparatus for removing a molded can from a mandrel, the first pneumatic means for pressurizing the space between the respective ends of the
Can and mandrel for moving the can from that
Core down and a valve for opening and closing the first pneumatic means, the core having a cutout for receiving an inwardly protruding portion of the can formed thereon, characterized by means for supplying one
flowable medium and channels for supplying the flowable medium, the channels through the mold core providing the means for supplying the under pressure
interconnect the standing fluid and the cutout to provide a pressurized fluid which expands the plastic can adjacent the cutout to facilitate removal of the can from the core by the primary pneumatic means, with the channels being sufficiently narrow
are to allow substantial flow of the liquid molding mixture into the channels during the molding process
impede. 130035/0524 30. The device according to claim 20, characterized in that the ejection device is valve-controlled pneumatic Means for pressurizing the space between the outer end of the mandrel and the bottom of the Can has. 130035/0524